The present invention relates to handles for hand-held tools and then particularly, but not exclusively, for files of the kind provided with a tang which is inserted into the handle, said handle including at least two parts which are separated in the tang-insertion direction and provided with tang guide means.
Several different designs of handles for hand-held files and like tools are known to the art. The majority of these handles fall into the following two main types.
The first and the simplest type of handle includes an axially extending hole or passage into which the file tang is pressed. The file tang is normally provided with a slightly conical, four-cornered attachment means. The handle thus has the simplest conceivable design, which enables it to be manufactured at low cost. One drawback with handles of this design, however, is that the handle cannot always be relied upon to grip the file firmly, and there is a risk of the file loosening in the handle and sliding therefrom while being used. This drawback has become particularly pronounced with handles that are made of plastic material, as is now more usually the case, which generates a low coefficient of friction between file and handle.
In the case of handles that belong to the second main type or category, the axially extending hole intended to receive the file tang is surrounded by thin, resilient jaws. The tang has a screw-threaded part and when the file has been inserted into the handle a nut is fitted over the file and tightened on the screw-threaded part of the tang. The resilient jaws are therewith pressed against the file and hold the file firmly in the handle. Manufacture of this handle, however, is a complicated process and the cost of manufacture is commensurately high.
U.S. Pat. No. 1,436,556 describes a file handle comprised of two halves of a metal shell which are pressed one against the other. Each shell half has cut therefrom two tongues which are pressed into the handle. By pressing the two shell halves together, a file can be inserted into the shaft and clamped firmly between said tongues, due to a tendency of the shell halves to spring back.
In addition to the manufacture of this handle being relatively complicated, another serious drawback with this known handle is that as the file is used it tends to loosen in the handle as a result of the workman involuntarily squeezing together the two handle halves with his/her hand during a working operation.